With growth of people's demand for an ever intelligent lifestyle, demand for high capacity of data processing is also growing. The global energy consumption in data processing has reached about hundreds of billions of or even trillions of kilowatts-hour each year, and a large data center can occupy an area up to tens of thousands of square meters. Accordingly, high efficiency and high power density are significant indicators of a health development of the data center industry.
A critical unit of the data center is a server, which is typically equipped with a mainboard composed of data processing chips (such as a CPU, chipsets, a memory or the like), their power supplies and necessary peripheral components. With increase of the processing capacity per unit volume of a server, the number and the integration level of the processing chips are also increasing, resulting in enlargement of occupied space and increase of power consumption. Accordingly, the power supply (also referred to as a mainboard power supply since it is on the same mainboard as the data processing chips) for the chips is expected to have higher efficiency, higher power density and smaller volume, so as to facilitate the energy saving and reduction of the occupied resource for the entire server or even of the entire data center.